Device for straightening bulged ends of railroad cars

ABSTRACT

A device to be positioned between the bulged end of a railroad car and an abutment structure or between facing ends of two uncoupled railroad cars to straighten the bulged ends thereof. Bumper members are supported by a frame and extend horizontally from opposite sides thereof to push the bulged ends inwardly, two counter-rotating winch drums and cables provide pulling of the two railroad cars toward each other to produce straighthening by the bumper members. A differential gear drive assembly couples together the two counterrotating winch drums to continue the pull of one in response to a greater resistance against the other. A hydraulic adjustment system supports the bumper members and is arranged to adjust the height and horizontal projections thereof independently of each other. Hydraulic rams are fixed to the frame to push the railroad cars away upon completion of a straightening operation and hydraulic pistons are adapted to maintain constant tension on the lateral corner edges of the cars to prevent deformation thereof.

United States Patent 7 [191 Bellemare 11] 3,741,029 [451 June 26, 1973 1 DEVICE FOR STRAIGHTENING BULGED ENDS OF RAILROAD CARS [21] Appl. No.: 136,439

[52] US. Cl. 72/419, 72/461, 72/705,

74/710, 242/54, 254/185 A [51] Int. Cl. B21d 1/14 [58] Field of Search 72/705, 419, 461;

[56] References Cited UNITED STATES PATENTS 3,525,249 8/1970 Bellemare 72/705 X 3,340,720 9/1967 Chartier 72/705 X 2,334,080 11/1943 Freeman 72/705 X 3,094,967 6/1963 Willis 74/710 X 3,443,698 5/1969 Lopez 254/184 X 3,502,302 3/1970 Hamersley 74/713 X FOREIGN PATENTS OR APPLICATIONS 7/1957 Austria 254/184 gate Primary Examiner-Charles W. Lanham Assistant Examiner-E. M. Combs Attorney-Pierre Lesperance [57] ABSTRACT A device to be positioned between the bulged end of a railroad car and an abutment structure or between facing ends of two uncoupled railroad cars to straighten the bulged ends thereof. Bumper members are supported by a frame and extend horizontally from oppo-- site sides thereof to push the bulged ends inwardly, two counter-rotating winch drums and cables provide pulling of the two railroad cars toward each other to produce straighthening by the bumper members. A differential gear drive assembly couples together the two counterrotating winch drums to continue the'pullof one in response to a greater resistance against the other. A hydraulic adjustment system supports the bumper members and is arranged to adjust the height and horizontal projections thereof independently of each other.I-lydrau1ic rams are fixed to the frame to push the railroad cars away upon completion of a straightening operation and hydraulic pistons are adapted to maintain constant tension on the lateral corner edges of the cars to prevent deformation thereof.

7 Claims, 12 Drawing Figures PAIENIED JUN 26 I973 SNEEI 2 0f 4 W MMM T E W w: L /ZW N m W m? o w Gm 5 l F AGENT PATENIEUJUNZS ma 3.741.029

sum 3 or 1 INVENTOR Gregoire BELLEMARE BY (7 p fi wum AGENT I r .H Ww J 1H I AGENT PAIENTEDJUNZB 1975 saw u or 4 INVENTOR Grgoire BELLEMARE BY DEVICE FOR STRAIGI-ITENING BULGED ENDS F RAILROAD CARS This invention relates to a device for repairing deformed railroad cars, and more particularly, to a device for straightening bulged ends of box cars.

Causes producing bulging of the ends of railroad cars, more particularly box cars, and the known methods and devices to reshape or straighten the bulged ends, are explained in my previous US. Pat. No. 3,525,249, issued on Aug. 25, 1970. The present invention is directed to an improved device of the type defined and claimed in the above United States Patent.

It is a general object of the invention to provide a device for straightening bulged ends of railroad cars of simpler and safer construction and operation.

It is a more specific object of the invention to provide a device of the above type which has bumper members and an assembly of simpler construction and operation to effect individual vertical and horizontal adjustment of the bumper members.

It is a further specific object of the invention to provide a device of the above type with an improved winch assembly to pull two railroad cars one towards another.

The invention will now be defined in detail with reference to a preferred embodiment illustrated, by way of example only, in the accompanying drawings, in which:

FIG. I is a perspective view of a device according to the invention positioned between the facing ends of two uncoupled cars;

FIG. 2 is a side elevation view of the device illustrated in FIG. 1;

FIG. 3 is a cross-sectional view as seen along line 33 in FIG.

FIG. 4 is an elevational view of the front side of the device as seen from the left in FIG. 2;

FIG. 5 is a partial cross-sectional view as seen along the line 5-5 in FIG. 4;

FIG. 6 is a cross-sectional view as seen along line 6-6 in FIG. 5;

FIGS/7, 8, and 9 are cross-sectional views as seen along lines 77, 8-8, and 99 respectively in FIG. 4;

FIG. 10 is a cross-sectional view as seen along line 10-10 in FIG. 9 and showing the details of a free wheeling clutch;

FIG. 11 is a cross-sectional view as seen along line ll-l1 in FIG. 5; and

FIG. 12 is a partial cross-sectional view as seen along line l212 in FIG. 11.

Referring now in detail to the accompanying draw ings, the device for straightening bulged ends of box cars according to the invention, identified generally by the numeral 1, is adapted to be preferably mounted between the facing ends of two uncoupled box cars 2 and 3 or between one box car and an abutment forming structure, such as a wall or another suitable, fixed or movable, structure. The box cars 2 and 3 are of the type having steel or metal ends 4, with or without corrugations 5, an end ladder 6 and a hand brake wheel 7. Lateral corner edges 8 of the ends 4 are formed along the lateral sides of the box cars 2 and 3.

The device 1 for straightening the bulged ends of railroad cars or box cars according to the invention, includes a cage-like frame 9 assembled into a rigid open structure, in any well known and suitable manner, to accommodate the other elements of the device. A

metal ring 10 is fixed to the top of the cage-like frame 9 and arranged to suspend the device therefrom for transport and positioning thereof at a desired height between two railroad cars 2 and 3. Suitable vertical channels or recesses 11 are provided into the front and rear sides of the frame 9 for the free passage of the manual brake wheels 7 upon vertical displacement of the frame 9 and positioning of the latter in operative position.

A plurality of horizontally extending bumper members 12 are mounted along the opposite front and rear sides of the frame 9. As illustrated in FIGS. 3, 5, and 6, the bumper members 12 include an edge 13 pointing away from the frame 9 and a rigifying plate 14 welded, or otherwise fixed, to the edge 13. The latter is shaped to engage into the concave portions of the corrugations 5.

As will now be explained in detail, the bumper members 12 are arranged for up-and-down displacement and for horizontal extension and retraction relative to the frame 9. For that purpose, the latter is provided on each side with a pair of parallel upward track or channel pieces 15 adjacent the ends of the bumper members 12, as best shown in FIGS. 5, 7, and 8. A pair of sliding blocks 16 are provided for each bumper member 12 and are slidably engaged into the corresponding upright tracks or channels 15. A horizontally extending hydraulic cylinder 17 is fixed against each sliding block 16 and is carried by the latter up and down along the guide track 15. The two sliding blocks 16 associated to anyone bumper member 12 are interconnected by a cross bar 18. Hydraulic cylinders 19 are fixed to the frame 9 in two laterally staggered vertical rows, as shown in FIGS. 5, 8, 11, and 12. Each hydraulic cylinder 19 is connected to a corresponding cross bar 18 to displace the latter up and down bodily with the associated pair of sliding blocks 16, hydraulic cylinders 17 and with the corresponding bumper member 12. It should be noted that the hydraulic cylinders 17 and 19 are of the double-action type to positively adjust the extension and the height respectively of each bumper member 12 independently or collectively.

Along each of both lateral edges of the front side and of both lateral edges of the rear side of the frame 9, there is provided one vertical row of stopper members, as illustrated in FIGS. 1, 2, 4, and 6. These stopper members may be constructed in the form of a succession of spaced-apart elements 20 or in the form of an elongated stopper member 21. The stopper elements 20 are provided where a ladder 6 faces the stopper members. Otherwise, an elongated construction, such as 21, is preferred. These stopper members 20, 21 are provided to protect the frame 9 during the straightening operation and to cooperate with the bumper members 12. Therefore, the stopper members should be positioned and extended with respect to the frame 9 as required to limit the displacement of the box cars towards the device 1.

For straightening the bulged ends of box cars, the device 1 is positioned at an appropriate height between two uncoupled box cars, such as the box cars 2 and 3, illustrated in FIGS. 1 and 2. The horizontal bumper members 12 are thereafter adjusted by actuation of the hydraulic cylinders 17 and 19. The two cars 2 and 3 are then pulled towards one another. This action is the.

mean effect of straightening the bulged ends of the cars by a winch mechanism which draws the two cars together. This winch mechanism will now be described with particular reference to FIGS. 4, 7, and 9.

The winch mechanism according to the present invention essentially includes a pair of independently rotatable winch drums 22 and 23 having respective cables 24 and 25 wound in the direction thereon. A common shaft 26 extends axially through both winch drums 22 and 23 and is rotatably mounted at its ends into bearings 27 fixed to the frame 9. The two winch drums are disposed in end to end relation immediately adjacent each other. A differential gear train 28 is coaxially mounted on the shaft 26 at one end of the two winch drums and a rotation reversing gear train 29 is coaxially mounted on the shaft 26 at the other end of the two winch drums.

The differential gear train 28 includes a pinion 30 fixed to the shaft 26 for rotation therewith, a second pinion 31 mounted for rotation about the shaft 26, a planet carrier 32 and planets 33 rotatably mounted around the shaft 26. A drive gear 34 is rotatably mounted onto the pinion 30 for rotation around the latter and supports the planet carrier 32 to transmit rotation thereto. The winch drum 22 is mounted around the shaft 26 and is drivingly connected to the pinion 31 of the differential gear train 28 by meansof a corresponding free wheeling clutch. The latter includes an inner piece 35 fixed to the pinion 31 for rotation therewith and an outer piece 36 fixed to an end flange of the drum 22 for rotation with the latter. The outer piece 36 is rotatably mounted relative to the pinion 31 and is arranged to be driven by the camming action of the inner piece 35 on the rollers or pins 37, as is known in the art.

The rotation reversing gear train 29 includes a pinion 38 rotatably mounted relative to the shaft 26 and a pinion gear 39 mounted on the shaft 26 for rotation therewith, and a pair of rotation reversing gears 40 rotatably mounted around a pair of pins or pivots fixed to the frame 9. A powerful motor 41 drives a gear reduction box 41 which drives'a gear 42 and a chain 43 engaging the drive gear 34 to rotate the latter and the winch drums 22 and 23 in a manner hereinafter explained in detail.

The operation of the winch mechanism and of the gear trains 28 and 29 thereof will now be explained with particular reference to FIG. 9, giving the clockwise and anticlockwise directions of rotation, as seen from the left in that Figure. In order to cause pulling of the cable 24 and winding thereof on the drum 22, the

latter must be rotated clockwise. This direction of rotation is obtained by clockwise rotation of the drive gear 34, which communicates the same clockwise rotation to the planet carrier 32 and the planet gears 33 around the shaft 26. This results in clockwise rotation of both pinions 30 and 31. The latter being fixed to the inner piece 35 of the associated free wheeling clutch causes the inner piece 35 to rotate the outer piece 36 and the drum 22 in clockwise direction by engagement of the rollers 37. Simultaneously, the clockwise rotation of the pinion 30 is communicated by the latter to the shaft 26 and to the pinion gear 39. The auxiliary gears 40 rotate about their pivots and thereby transmit an anticlockwise rotation to the pinion gear 38. The free wheeling clutch associated to the pinion 38 is arranged in reverse direction relative to the other free wheeling clutch; therefore, the anticlockwise rotation of the pinion 38 is transmitted to the drum 23, resulting in winding of the cable 25.

When winding of one cable, either 24 or 25, encounters a greater resistance than the other, the differential gear train 28 operates by rotation of the planets 33 about theirpivots, to transmit a greater rotation to either pinion 30 or 31, as the case may be, and thereby to the corresponding drum operatively connected thereto. Thus when one drum stops, the other drum continues to rotate.

It must be noted that the cables 24 and 25 are arranged in the same tangential plane at the drums 22,23, thereby avoiding the need of an extra pulley'and the related disadvantages. This enables to position the winch mechanism on the center transverse vertical plane of the cage like frame 9 and consequently the overall width of frame 9, that is the distance between the stopper members 20, 21 at each side of frame 9 can be reduced, resulting in a lighter and less expensive frame 9. It will also be noted that because the drums are mounted immediately adjacent each other and are counterotating, the two cables extend from the respective drums with a minimum of lateral offset from the center vertical longitudinal plane of the frame and are also in the same tangential plane to the drums. Consequently, the two cables are maintained practically in alignment when exerting a straightening pull on the cars. This is important to avoid any lateral force on the cars. It will also be understood that the unwinding of the cables 24 and 25 can readily be made, without operating the motor 41, by merely pulling on the free ends or hooks thereof due to the disengagement of the free wheeling clutches in their reverse direction.

The winch mechanism with the differential gear train and two oppositely rotating winch drums, overcomes the following disadvantages of the system described in my previous U.S. Pat. No. 3,525,249.

When the two railroad cars have unequally bulged or deformed ends, the cage-like frame of my previous Patent first contacts, during car pulling, the more deformed car end, and being still out of contact with the other car, takes an inclined position to the vertical, because the cables pull from the bottom of the cage-like frame and the latter is suspended by a flexible cable. This might result in improper positioning of the bumper members within the corrugations of the car end and eventual deficient straightening of said car end.

Also, the portions of two cables extending from the single winch drum must always be of equal length in order to obtain equal straightening of the two cars. Finally, one of the two cables must be trained on an idler pulley in order to be wound on the winch drum in the same direction as the other cable.

In the present system, the last two requirements are eliminated and the cage-like frame will not become unduly inclined during pulling and straightening, despite unequal bulginess of the two car ends and also despite unequal resistance to straightening.

In order to avoid deformation of the lateral corner edges 8 of the box car ends, the straightening device 1 is provided with hydraulic piston assemblies adapted to control the tension between the lateral corner edges 8, more particularly the center portion of the lateral corner edges, and the device 1. Two hydraulic cylinders 48, positioned end to end, are fixed on each side of the frame 9 and a chain 49, or the like, connects one outer end of each piston to the corresponding lateral corner edge 8 by a suitable hook 50.

A hydraulic fluid supply 51 is mounted onto the frame 9, as illustrated in FIGS. 4 and 8, to supply hydraulic fluid to actuate the various hydraulic cylinders forming part of the straightening device 1. The hydraulic fluid supply 51 includes a motor 52 connected to a pump 53 to rotate the latter and supply hydraulic fluid to the hydraulic cylinders. The various fluid lines and valves which are required to transmit the hydraulic fluid and to control the actuation of the various hydraulic cylinders do not form part of the present invention and are not shown for the sake of clarity.

What I claim is:

1. A device for straightening the bulged ends of railroad cars comprising, in combination, a frame, horizontal bumper means mounted onto said frame and projecting from the opposite sides of the latter, means for positioning said frame at a suitable height into a space defined between the ends of two railroad cars, at least one of which has a bulged end to be straightened, with said bumper means facing said railroad car ends, a first pulling means arranged to be connected to one railroad car, a second pulling means arranged to be connected to the other railroad car, said first and second pulling means being mounted onto said frame and constructed and arranged to pull said two railroad cars towards each other to cause them to engage said bumper means and to cause said horizontal bumper means to push said bulged end inwardly relative to said one railroad car to straighten said bulged end, said first and second pulling means including a'common shaft journalled in the bottom'portion of said frame and disposed parallel tosaid sides, first and second winch drums coaxially and rotatably mounted on said common shaft and disposed in end-to-end relation immediately adjacent each other, first and second cables wound in opposite direction on said first and second drums respectively and arranged to extend away from the respective drums infthe same tangential plane, adifferential gear train mounted onisaid common shaft adjacentthe. free end of said first winch'drum and arotationreversing gear train mounted onto said common shaft adjacent the free end of said-second winch drum,'said reversing gear; train drivingly connected to said common shaft and to said second winch drum, said differential gear trainhaving an input driven by a driving means and differential outputs drivingly connected to said common shaft and to said first winch drum respectively.

2. A device as claimed in claim 1, wherein the driving connection between said reverse gear train and said second winch drum and the driving connection between one of said differential outputs and said first winch drums'arefreewheeling clutches adapted to drive the respective winch drums in their cable winding direction and to allow free rotation of said winch drums in their cable unwinding direction.

3. A device as claimed in claim 2, wherein said differential gear'trainfincludes a first pinion fixed to said members defining separate edges pointing horizontally away from and along the sides of the frame, and each of said bumper members is provided with a hydraulic cylinder means connected between the same and said frame and arranged to adjust the height of the corresponding bumper member relative to said frame independently of the other bumper members. a

5. A device as claimed in claim 4, furtherincluding on each side of said frame a pair of upward guide tracks fixed to said frame adjacent the opposite ends of said bumper members, a pair of sliding blocks for each of said bumper members slidably engaging said guide tracks, a pair of hydraulic cylinders for each of said bumper members and connected at one end to the latter and at the other end to the corresponding pair of sliding blocks, and arranged to produce independent horizontal extension and retraction of said bumper members relative to said frame, a cross bar for each of said bumper members interconnecting the two sliding blocks of the corresponding pair of sliding blocks, and arranged for bodily movement therewith, each of said hydraulic cylinder means being a hydraulic cylinder connected at one end to a corresponding cross bar and at the other endto said frame to produce up and down displacement of the corresponding cross bar, a pair of sliding blocks, a pair of hydraulic cylinders and a bumper member.

6; A device for straightening the bulged ends of railroad cars comprising, in combination, a frame, horizontal bumper means mounted onto said frame and projecting from the opposite sides of the latter, means for positioning said frame at a suitable height into a space defined between the ends of two railroad cars, at least one of which has a bulged end-to be straightened, with said bumper means facing said railroad car ends, a first pulling means arranged to be connected to one I railroad car, a second pulling means arranged to be common shaft for rotation therewith, a second pinion I mounted onto said common shaft for rotation around the latter, a planet carrier and planet gears rotatably carried by said planet carrier in meshing engagement connected to the other railroad car, said first andsecond pulling means being mounted onto said frame and constructedand arranged to pull said two railroad cars towardssaid frame and towards each other to engage said bumper members and to cause'said horizontal bumper means to push said bulged end inwardly relative to said one railroad car, coupling means joining said first pulling means to said second pulling means and arranged to continue pulling one railroad car towards said frame when the other railroad car has ceased to move towards said frame, said horizontal bumper means including a plurality of bumper members defining separate edges pointing horizontally away from and along said one side of the frame, each of said bumper members is provided with a hydraulic cylinder means connected between the same and said frame and arranged to adjust the height of the corresponding bumper member relative to said frame independently of the other bumper members, a pair of upward guide tracks is fixed to said frame adjacent the opposite ends of said bumper members, a pair of sliding blocks for each of said bumper members slidably engage said guide tracks, a pair of hydraulic cylinders for each of said bumper members is connected at one end to the latter and at the other end to the corresponding pair of sliding blocks and is arranged to produce independent horizontal extension and retraction and to allow independent vertical displacement of said bumper members relative to said frame, a cross bar for each of said bumper members interconnects the two sliding blocks of the corresponding pair of sliding blocks and arranged for vertical bodily movement therewith, and each said hydraulic cylinder means is a hydraulic cylinder connected at one end to a corresponding cross bar and at the other end to said frame to produce up-and-down displacement of the corresponding cross bar, a pair of sliding blocks, a pair of hydraulic cylinders and bumper member. 7. A device as claimed in claim 6, further including ,a hydraulic fluid pressure supply arranged to be con- 

1. A device for straightening the bulged ends of railroad carS comprising, in combination, a frame, horizontal bumper means mounted onto said frame and projecting from the opposite sides of the latter, means for positioning said frame at a suitable height into a space defined between the ends of two railroad cars, at least one of which has a bulged end to be straightened, with said bumper means facing said railroad car ends, a first pulling means arranged to be connected to one railroad car, a second pulling means arranged to be connected to the other railroad car, said first and second pulling means being mounted onto said frame and constructed and arranged to pull said two railroad cars towards each other to cause them to engage said bumper means and to cause said horizontal bumper means to push said bulged end inwardly relative to said one railroad car to straighten said bulged end, said first and second pulling means including a common shaft journalled in the bottom portion of said frame and disposed parallel to said sides, first and second winch drums coaxially and rotatably mounted on said common shaft and disposed in endto-end relation immediately adjacent each other, first and second cables wound in opposite direction on said first and second drums respectively and arranged to extend away from the respective drums in the same tangential plane, a differential gear train mounted on said common shaft adjacent the free end of said first winch drum and a rotation reversing gear train mounted onto said common shaft adjacent the free end of said second winch drum, said reversing gear train drivingly connected to said common shaft and to said second winch drum, said differential gear train having an input driven by a driving means and differential outputs drivingly connected to said common shaft and to said first winch drum respectively.
 2. A device as claimed in claim 1, wherein the driving connection between said reverse gear train and said second winch drum and the driving connection between one of said differential outputs and said first winch drums are free wheeling clutches adapted to drive the respective winch drums in their cable winding direction and to allow free rotation of said winch drums in their cable unwinding direction.
 3. A device as claimed in claim 2, wherein said differential gear train includes a first pinion fixed to said common shaft for rotation therewith, a second pinion mounted onto said common shaft for rotation around the latter, a planet carrier and planet gears rotatably carried by said planet carrier in meshing engagement with said first and second pinions, said planet carrier constituting the input of said differential gear train, said second pinion drivingly connected to said first winch drum through one of said free wheeling clutches.
 4. A device as claimed in claim 1, wherein said horizontal bumper means include a plurality of bumper members defining separate edges pointing horizontally away from and along the sides of the frame, and each of said bumper members is provided with a hydraulic cylinder means connected between the same and said frame and arranged to adjust the height of the corresponding bumper member relative to said frame independently of the other bumper members.
 5. A device as claimed in claim 4, further including on each side of said frame a pair of upward guide tracks fixed to said frame adjacent the opposite ends of said bumper members, a pair of sliding blocks for each of said bumper members slidably engaging said guide tracks, a pair of hydraulic cylinders for each of said bumper members and connected at one end to the latter and at the other end to the corresponding pair of sliding blocks, and arranged to produce independent horizontal extension and retraction of said bumper members relative to said frame, a cross bar for each of said bumper members interconnecting the two sliding blocks of the corresponding pair of sliding blocks, and arranged for bodily movement therewith, each of said hydraulic cylinder means being a hydraulic cylinder connected at one end to a Corresponding cross bar and at the other end to said frame to produce up and down displacement of the corresponding cross bar, a pair of sliding blocks, a pair of hydraulic cylinders and a bumper member.
 6. A device for straightening the bulged ends of railroad cars comprising, in combination, a frame, horizontal bumper means mounted onto said frame and projecting from the opposite sides of the latter, means for positioning said frame at a suitable height into a space defined between the ends of two railroad cars, at least one of which has a bulged end to be straightened, with said bumper means facing said railroad car ends, a first pulling means arranged to be connected to one railroad car, a second pulling means arranged to be connected to the other railroad car, said first and second pulling means being mounted onto said frame and constructed and arranged to pull said two railroad cars towards said frame and towards each other to engage said bumper members and to cause said horizontal bumper means to push said bulged end inwardly relative to said one railroad car, coupling means joining said first pulling means to said second pulling means and arranged to continue pulling one railroad car towards said frame when the other railroad car has ceased to move towards said frame, said horizontal bumper means including a plurality of bumper members defining separate edges pointing horizontally away from and along said one side of the frame, each of said bumper members is provided with a hydraulic cylinder means connected between the same and said frame and arranged to adjust the height of the corresponding bumper member relative to said frame independently of the other bumper members, a pair of upward guide tracks is fixed to said frame adjacent the opposite ends of said bumper members, a pair of sliding blocks for each of said bumper members slidably engage said guide tracks, a pair of hydraulic cylinders for each of said bumper members is connected at one end to the latter and at the other end to the corresponding pair of sliding blocks and is arranged to produce independent horizontal extension and retraction and to allow independent vertical displacement of said bumper members relative to said frame, a cross bar for each of said bumper members interconnects the two sliding blocks of the corresponding pair of sliding blocks and arranged for vertical bodily movement therewith, and each said hydraulic cylinder means is a hydraulic cylinder connected at one end to a corresponding cross bar and at the other end to said frame to produce up-and-down displacement of the corresponding cross bar, a pair of sliding blocks, a pair of hydraulic cylinders and bumper member.
 7. A device as claimed in claim 6, further including a hydraulic fluid pressure supply arranged to be connected to said hydraulic cylinders and arranged to selectively actuate the same, and a pair of hydraulic pistons and cylinder units mounted onto said frame at each end thereof and arranged to be connected to the adjacent lateral corner edges of said railroad cars to maintain said corner edges under tension and prevent deformation thereof during the straightening operation. 